Total Hip and Total Knee Arthroplasty in Juvenile Rheumatoid Arthritis

Abstract

Total hip arthroplasty (THA) or total knee arthroplasty (TKA) is indicated for patients with juvenile rheumatoid arthritis (JRA) when marked joint destruction is present and pain or deformity compromises function despite optimal medical therapy. Relief of pain, reduction of the deformity, and dramatic improvement in functional status and quality of life can be achieved in most patients. Functional impairment and deformity rather than pain are usually the primary indications for THA or TKA. When there is both hip and knee involvement, hip arthroplasty should probably be done first. Regional anesthetic appears to be the anesthetic of choice. Careful preoperative planning and the availability of custom and minisized components are essential. Small bone size, osteoporosis, and severe soft tissue disease make the surgery technically demanding. Skeletal immaturity may not contraindicate surgery if the patient is otherwise bedridden with progressive deformity. In the hip trochanteric osteotomy is often necessary for adequate exposure, with the possible exception being a patient with juvenile ankylosing spondylitis who is subject to heterotopic bone formation. Although complete capsulectomy and psoas tenotomy may be necessary to relieve a hip flexion contracture, a soft tissue release that produces leg lengthening may lead to nerve palsy. In the hip component loosening has been less common in patients with JRA than in other young patients who have undergone THA, but it is still the most frequent cause of failure. In the knee preoperative and postoperative serial casts can aid in the correction of severe flexion contracture. Secondary patellar pain has been the most common cause of late failure. Patellar resurfacing should probably be performed at the time of the original knee arthroplasty in all patients with JRA.